We turn now to a poison that some say pack a powerful medicinal punch. Some people claim it fights everything from impotence to cancer. Forests are crawling with these creatures and that's where matt reports from tonight. Reporter: Turn on the black light and see if they are here. Look at them. Oh my god. To most of us, these scorpions in the jungle of darkness is the stuff of nightmares but now they are also being touted as the stuff of salvation. Everything from battling auto immune diseases and enhancing your love life and a new weapon. And the soul active ingredient is the venom packed into the scorpion's stinger. I have seen people getting well immediately. The doctor and his company made the controversial claim that the chemical in the venom that causes paralysis in prey targets and kills cancer cells and they have managed to harness that into a drug. Are you convinced? More than convinced. A drug not approved but available for sale in the u.S. For $700 a bottle. A substance that thousands of desperate people, many of them americans, are literally betting their lives on. There you go. Peggy, a grandmother from texas, is one of those people. I have absolutely no doubt that it saved my life. In 2011, she was diagnosed with stage four breast cancer. She says doctors told her and her husband larry she had just two months to live. I arranged for what I wanted for a funeral. As a last ditch effort, peggy started taking the drug. Within six months it was gone. There was absolutely no more cancer left. Did corps onven-- scorpion venom really get her cancer? We decided to find out more for ourselves. Wow. But getting close to the source, that venom, is no simple feat. This is spectacular. It does not come from just any venom but the venom of blue scorpi scorpions. Pretty amazing. From above the lush forests carpet these peaks. On the ground, a more prickling reality. We were greeted by young villagers. He just came up to me with a salt shaker and inside? Three scorpions. Don't try this at home. And the boys so used to handling these creatures offer me a hands on tutorial on scorpion wrangling. And then on to what must surely be the only scorpion reservation in the world, come complete with 83,000 residents. You do it. There's one. Turn over a stone or peer into a bamboo segment, and there they are. They are quite mysterious. He and his parter in swear the drug is down right miraculous. It goes up to 95, 98%. It kills 95 to 98% of cancer cells? Yes. Pretty big claim. We know. In addition to attacking cancer cells, it is said that scorpion venom may battle auto immune disease. The company claims it can even help with male potency. Big pharma spends billions of dollars. How much they have not found the magic scorpion cure and you have? Usually big companies they don't work with natural compounds because you can't patent natural product. This is not the first natural remedy purported to kill diseases. Some have turned out to have significant value, most have been bunked. When you tell people that this medicine is going to help them cure cancer, they have no reservation doing it. We never use cure cancer. Helps your body use its natural ability to cure cancer, people will see cure cancer. Fight cancer. Eating vegetables can help you fight cancer. That is what the sub text is in this drug. I mean, obviously we want to help the maximum abilities that this medicine can possibly help. And they say it has been helping people here in the dominican republic for generations. She says she always have a scorpion. Like the shopkeeper who keeps them bottled inner the pen tine with her at all times. It will even help my runner's knee. It didn't, but it did keep the mow s mosquitos away. Next up, this rented lab, the venom is extracted. Why don't you have a go now. Are you serious? Okay. They wanted me to milk a scorpion. We're going to be friends. I'm just going to milk you. I don't want to squish him. This is not as easy as it looks. Five to seven drops of the venom are extracted from them every month. Only a tiny amount is inserted into these bottles, each of these goes for $700. The bottles are sold on the internet and then sold to patients like peggy. She doesn't give up easy. It has given me my life back. I got to see my granddaughter born. I wouldn't be here at all if it were not for the medicine. She had a scorpion tattooed on her ankle. Do I believe in it? But none of the medical files seem so show that it healed her. There is no scientific evidence to show that this drug works. Dr. Len is a deputy medical director of the american cancer society and he has seen too many claims like this that turned out not to work. Cancer patients have enough to deal with to have to deal with unverified and undocumented hope is is a burden that no one should have to bare. The doctor's skepticism was not the only thing that gave us pause. Right there it says it is a natural medicine approved and certified for oncology treatments. It received this approval only in the dominican republic. Are you approved in any other countries to make these claims? Russia, and vietnam. When we alerted them that its website may violate fda regulations against marketing drugs, the company conceded it was rapidly making changes to the site but there was a much more important issue. They could not produce a single peer reviewed study that proves it works. The results of their trial are not acceptable by american standards of science. It's one reason the doctors say they warn patients to be wary of unproven remedies. Many more times than not, the original claims that were made for some of these drugs don't work out. Just an amazing factory. The doctor aknologies the drug needs significantly more testing before they can even apply for fda approval. Shake it up. But this woman does not have the time to wait. Her cancer is now back. After a hiatus from the drug, she is putting her faith in the venom of scorpions once again, hoping it will save her life. Thanks for that. Next, we're infiltrating a

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